The invention relates to an electromagnetic interference shielding device in the form of a contract spring element for closing a gap or clearance between housing or covering-panel members of a cabinet or rack containing electronic equipment.
From German Pat. No. 2,039,681 there is known one such shielding device, which consists of spring contact elements freely cut out of a sheet metal strip having an L-shaped cross section. The shielding device is capable of being inserted into the grooves of housing members. One housing member, e.g. a corner profile, comprises specially shaped grooves in which the contact spring strips as well as the respective neighbouring housing members (closing plates) are slipped. With the aid of the contact spring strips, the housing members are connected in an electrically conductive manner and, at the same time, electromagnetic interference shielding for the interior of the housing is provided. The disclosed type of shielding device, however, is only suitable for use with fixed housing members, hence not with doors or similar moving parts.
For the electromagnetic interference shielding of door joints there is disclosed, for example, in the German Pat. No. 2,522,186, a sealing element which is disposed in the door. In this construction, behind an angled-off door edge, there is mounted a flexible ledge. Between this ledge and a parallel-extending angle section there is clamped the flap of an electrically conducting sealing strip which is rolled over at its free end and, in this part, may be filled with an elastic core. Upon closing the door, the rolled part is compressed and establishes the contact between the door and the housing.
Another door-joint shielding is known from German Offenlegungsschrift No. 3,219,263 which, however, is only for use on the hinge side. On this side, the door panel is bent at least semicircularly, with the rounding being covered by a spring plate connected on one hand to the door and, on the other hand, to the door frame.
Finally, from German Offenlegungsschrift No. 3,210,843, there is known a contact device for housing members capable of being moved in relation to one another, in which a knife-shaped extension of one housing member comes into snap-engagement with a groove lined with contact springs, of the other housing member.